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If a new aquarium and it is diatoms, just wipe off as it grows - will clear up in a few weeks/month or so. If true algae, than lights on too long or an nutrient imbalance (if using ferts) or too much waste food or high nitrates all can be issues.

Knowledge is fun(damental)

A 75 gal with eight Discus, fake plants, and a lot of wood also with sand substrate. Clean up crew is down to just two Sterba's Corys. Filters: continuous new water flow; canister w/UV, in-tank algae scrubber!! Finally, junked the nitrate removal unit from hell.

If a new aquarium and it is diatoms, just wipe off as it grows - will clear up in a few weeks/month or so. If true algae, than lights on too long or an nutrient imbalance (if using ferts) or too much waste food or high nitrates all can be issues.

How long should the lights stay on for?

Here's my reading I just took from the tank.

NO2: 0
NO3: 80
PH: 7.0

I did wipe it off the tank but it's on almost every live plant in the tank.

Light duration is determined by the plant type and light intenisty but in gerenal, 6 hours to 8 hours.

Your nitrates are far, far too high. It should be under 20 and ideally under 10 ppm. You need to clean off as much algae as possible, do a 90%+ water change and besure the nitrates don't climb above 20 ppm. You need to up your weekly water changes and/or cut back on food for the fish (may be an issue and maybe not.) Does sound like a cyanobacteria growth more than algae. Do you uses ferts for the plants? CO2 (injected or liquid) can kill cyanobacteria.

Last edited by Cermet; 10-16-2012 at 11:43 PM.

Knowledge is fun(damental)

A 75 gal with eight Discus, fake plants, and a lot of wood also with sand substrate. Clean up crew is down to just two Sterba's Corys. Filters: continuous new water flow; canister w/UV, in-tank algae scrubber!! Finally, junked the nitrate removal unit from hell.

Light duration is determined by the plant type and light intenisty but in gerenal, 6 hours to 8 hours.

Your nitrates are far, far too high. It should be under 20 and ideally under 10 ppm. You need to clean off as much algae as possible, do a 90%+ water change and besure the nitrates don't climb above 20 ppm. You need to up your weekly water changes and/or cut back on food for the fish (may be an issue and maybe not.) Does sound like a cyanobacteria growth more than algae. Do you uses ferts for the plants? CO2 (injected or liquid) can kill cyanobacteria.

Thanks. The light is on for about 8 hours a day...

I just started a fert for the plants over the weekend. Had the algae before that though. It's a liquid fert.

I feed the fish in the morning and its not a lot. If they dont eat it all while I'm there I cut it back. They do a good job of cleaning it up and the snail gets what they dont.

When you clean the filter media, rinse in dechlorinated water only (use waste tank water.) Lady Hobbs is correct - the filter media can create massive nitrates. Water changes, long term, are the key to a healthy aquarium.

Be very careful with liquid ferts - if you have algae, these can feed them. Use only what the plants need. Under fert and watch for algae growth - if it reduces the algae as the plants do better, maybe raise it some.

While 8 hours is max light duration, this assumes the lights are the correct color temperature and intensity (watts per gal and correct for plant type.) Old bulbs lose their intensity. If the lights are not designed for plants, algae will get the upper hand.

Forgot to ask - does your water supply have high level nitrates? If so, this is an import issue.

I hate algae and it can be a battle - get those nitrates down and have the correct color temperature, be careful with ferts (borad spectrum ones can be an issue) and large water changes weekly all will help fight that monster. Best of luck!

Last edited by Cermet; 10-17-2012 at 11:11 AM.

Knowledge is fun(damental)

A 75 gal with eight Discus, fake plants, and a lot of wood also with sand substrate. Clean up crew is down to just two Sterba's Corys. Filters: continuous new water flow; canister w/UV, in-tank algae scrubber!! Finally, junked the nitrate removal unit from hell.